As the technician in the sector knows, the hulls of boats generally undergo a plurality of works which are intended to give them the desired aesthetic look such as, e.g., sanding, sandblasting, surfacing and painting.
Each stage must be performed with extreme care in order to avoid the presence of faults which can greatly affect the final aesthetic quality.
The present invention relates particularly, but not solely, to the execution of the painting stage, by means of which, on the hull already worked and theoretically without surface faults, a paint is applied to give its final aesthetic look.
Up to now, the painting stage is hand-made by an operator or using a number of tools suited to spray the paint on the intended surface.
As can be easily understood, hand-painting has a series of drawbacks.
It requires, in fact, long execution times which affect the final cost of working, and its successful outcome strongly depends on the skills of the operator performing it.
Also the painting made using a suitable tool for paint spraying has however a number of drawbacks.
The application of paint by spraying implies that a part of atomized particles of paint do not adhere to the surface to be painted, thus dispersing in the surrounding environment (this phenomenon being defined as “overspray”).
Since the paints used for these applications generally contain toxic or polluting substances, it can be easily understood how their dispersion can be harmful to the environment and people who work in the vicinity of the painting area.
In this regard, in fact, recent community standards provide for more and more restrictive measures as far as the emission of such substances in the environment is concerned.
Some devices for the painting of hulls of boats or the like are known from DE 4328410, DE 19738962, JP 6269709 and WO 01/34309.
In particular DE 4328410 describes a device for the dispensing of paint or the like, wherein the nozzle (or nozzles) from which the dispensed product flows out is contained in a kind of cabin. Dispensing means are provided along the profile of the cabin of a liquid suited to capture the particles in excess of the dispensed product and which is suctioned through the relative suction means. This device does not allow an efficient and quick work of the surface to be worked, since the cabin and dispensing nozzle move integrally with one another and therefore both must be moved each time the working area must be modified.
Furthermore, this solution does not allow a correct dispensing of the product, since the liquid dispensed inside the cabin can interfere with the outflow of the paint, thus altering the working of the surface.
DE 19738962 describes a solution similar to the one of DE 4328410, wherein the product dispensing nozzle is arranged inside a containment cabin and moves integrally with it and wherein along the cabin profile a plurality of suction funnels are arranged.
This device also is difficult to use, as is DE 4328410, due to the frequent handling of the nozzles-cabin unit which must be done to work different areas of the above-mentioned surface.
Furthermore, it does not allow to obtain an efficient prevention of overspray, since it does not make any control of the air entering into the cabin.
Again, this solution is complex to be manufactured.
JP 6269709 describes a device in which the product dispensing element moves inside a relative containment cabin and in which a plurality of nozzles are provided suited to dispense pressurized air inside the cabin.
This solution, besides being very complex and costly from a manufacturing point of view, is also not much efficient, since besides not preventing the phenomenon of overspray, it also causes a high turbulence inside the cabin that jeopardizes the correct dispensing of the paint on the surface to be worked.
WO 01/34309 also describes a device for the dispensing of paint or the like, wherein the nozzle from which the dispensed product flows out is contained in a kind of cabin with air suction means.
WO 01/34309 also describes an embodiment in which the containment cabin has sensors suitable for adjusting the position of the nozzle for dispensing the product so as to keep it steady with respect to the surface to be worked.
This device also has a number of drawbacks. It is not so easy as it requires the continuous movement of the cabin-nozzle unit to intervene on different areas of the worked surface.
Furthermore, it does not allow an efficient prevention of overspray since it does not control the air flow rates, either the suctioned one and the one entering into the cabin.
It is therefore possible that situations may arise wherein one part of the dispensed product is suctioned by the suction means and others wherein the particles of dispensed product flow out of the cabin.